Sharks are disappearing from the world’s oceans. The numbers of many large shark species have declined by more than half due to increased demand for shark fins and meat, recreational shark fisheries, as well as tuna and swordfish fisheries, where millions of sharks are taken by accident each year.

Now, the global status of large sharks has been assessed by the World Conservation Union, which is widely recognized as the most comprehensive, scientific-based information source on the threat status of plants and animals.

“As a result of high and mostly unrestricted fishing pressure, many sharks are now considered to be at risk of extinction,” explained Julia Baum, a member of the union’s Shark Specialist Group

“Of particular concern is the scalloped hammerhead shark, an iconic coastal species, which will be listed on the 2008 IUCN Red List as globally endangered due to overfishing and high demand for its valuable fins in the shark fin trade,” added Ms. Baum, who is a postdoctoral fellow at Scripps Institution of Oceanography.

Ms. Baum pointed out that fishing for sharks in international waters is unrestricted, and she supports a recently adopted United Nations resolution calling for immediate shark catch limits as well as a meaningful ban on shark finning, the practice of removing only a shark’s fins and dumping the still live but now helpless shark into the ocean to die.

Costa Rica is a major supplier to the international shark fin trade.

Research at Canada’s Dalhousie University over the past five years, conducted by Ms. Baum and the late Ransom Myers, demonstrated the magnitude of shark declines in the northwest Atlantic Ocean. All species the team looked at had declined by over 50 per cent since the early 1970s. For many large coastal shark species, the declines were much greater: tiger, scalloped hammerhead, bull and dusky shark populations have all plummeted by more than 95 per cent.

A commercial fish factory vessel was boarded this month by Costa Rican officials because they said it was involved in illegal fishing in the protected area of Isla del Coco. However, investigators had to let the 25-person crew go because there was uncertainty in the law regarding this kind of activity. The crew was seeking tuna but sharks, including hammerheads for which the waters around the island are famous are likely victims, too.

The government of South Korea has joined the rush to “bioprospect” the country’s wealth of biodiversity.

According to online encyclopedias, bioprospecting is the collection of samples from animals, plants and microorganisms to be used to create new drugs, crops or industrial products.

Representatives from the South Korean government announced a partnership with the National Biodiversity Institute, a nonprofit organization dedicated to cataloguing and facilitating the exploitation of the country’s dizzying variety of wildlife and plant species.

Bioprospecting manager Lorena Guevara said the South Koreans are investing $643,000 to expand the Institute’s current facilities in Santo Domingo de Heredia and another $1 million in projects, specifically tied to plant research. At least one Korean scientist will also be added to the staff.

With multinational corporations, such as Eli Lilly, Merck, Bristol-Mayer, and universities such as Harvard already partnering with the institute, Guevara said South Korea decided it was time to get on board.

Guevara said the best-known commercial results from bioprospecting so far in Costa Rica include two products – Quassia, a tree extract that helps with hangovers, and Estilo, an herb that serves as a sedative.

“Our mission is the systematic search for genes, molecules, chemical compounds that can be of pharmaceutical, agricultural or biotechnology use,” she said. “We have found some very interesting compounds, especially from microorganisms.”

The manager said the Institute is working on identifying compounds that could be used as cures for cancer, Alzheimer’s, AIDS, malaria and asthma.

In recent years, scientists and conservationists have been working to raise public awareness of a global decline in amphibian populations. Herpetologists first started noting that amphibian populations were falling at many of their study sites in the 1980s. Those early reports were anecdotal and many experts doubted that the observed declines were cause for concern (the argument was that populations of amphibians fluctuate over time and the decline could have been merely natural variation).

But by 1990, a significant global trend had emerged—one that overstepped normal population fluctuations. Herpetologists and conservationists started voicing their concern for the worldwide fate of amphibians. Their message was alarming: of the estimated 5,918 known species of amphibians that inhabit our planet, a staggering 1,856 species were listed as endangered, threatened or vulnerable on the IUCN Red List (Global Amphibian Assessment 2007).

Amphibians are considered to be indicator species for environmental health: they have delicate skin that readily absorbs toxins from their environment; they have few defenses and can fall prey to non-native predators; they rely on both aquatic and terrestrial habitats at various times during their life cycle. If amphibians populations are in decline, it is likely that the quality of the habitat in which they live is suffering.

There are numerous known factors that contribute to amphibian declines—habitat destruction, pollution, the effects of introduced species. Yet research has revealed that even in pristine habitats—those that lie beyond the reach of the bulldozer and crop-duster—amphibians are disappearing at a shocking rate and without explanation. Scientists are now looking to global phenomena for explanations. Climate change, emerging diseases, and increased exposure to UV-B radiation (due to ozone depletion) are all additional factors that could be contributing to falling amphibian populations.

So it seems the question ‘Why are amphibians in decline?’ has no simple answer. Instead, amphibians are disappearing due to a complex mixture of factors which include:

Alien Species—Native amphibian populations can suffer decline when alien species are introduced into their habitats. There are a number of ways an introduced species can impact populations of native amphibians. For instance, an amphibian species may become the prey of the introduced species. Alternatively, the introduced species may compete for the same resources required by the native amphibian. It is also possible that the introduced species may form hybrids with the native species and in doing so reduce the prevalence of the native amphibian within the resulting gene pool.

Over-Exploitation—Amphibian populations in some parts of the world suffer decline because they are captured for the pet trade or are harvested for human consumption.

Habitat Alteration and Destruction—Alteration and destruction of habitat has devastating effects on many organisms and amphibians are no exception. Changes to water drainage, vegetation structure, and habitat composition all impact the ability of amphibians to survive and reproduce. For example, the drainage of wetland areas for agricultural use of the land directly reduces the habitat available for amphibians which require aquatic habitat for breeding and foraging.

Global Changes (Climate, UV-B, and Atmospheric Changes)—Global climate change presents a serious threat to amphibians because altered precipitation patterns will likely result in changes to wetland habitat on which amphibians rely. Additionally, increases in UV-B radiation due to ozone depletion have been found to severely impact some species of amphibians.

Infectious Diseases—Significant amphibian declines have been associated with infectious diseases such as chytrid fungus and iridoviruses. Chytrid fungal infections in amphibians was first discovered in populations of amphibians in Austrailia but also has been found in Central America and North America.

Pesticides and Toxins—The widespread use of pesticides, herbicides, and other synthetic chemicals and pollutants has severely impacted many amphibian populations. In 2006, scientists at the University of California, Berkeley found that mixtures of pesticides were causing amphibian deformities, reducing reproductive success, harming development, and increasing susceptability to diseases such as bacterial meningitis.

SAN JOSE, Costa Rica (Reuters) – Costa Rican President Oscar Arias has ordered the expropriation of lucrative beach-front land to protect the endangered leatherback sea turtle, the government said on Thursday.Arias began expropriation procedures for some 30 hectares (74 acres) of land in northwestern Costa Rica, the most important leatherback sea turtle nesting site on the Pacific Rim, Energy and Environment Minister Roberto Dobles said.”We are only complying with the law that established Las Baulas (national marine park) in 1995,” Dobles told Reuters.

Some of the expropriated land owners, mostly Europeans and U.S. citizens, had resisted the expropriation even though the land was made a national park by law in 1995.

Environmentalists hailed the move to protect the turtles, which have been declining in alarming numbers in recent years.

“It will help us to restore the population of leatherback turtles in the Pacific,” said Todd Steiner of the San Francisco-based Turtle Island Restoration Network.

Environmentalists say 95 percent of leatherbacks in the Pacific Ocean have vanished in the last 20 years due to human activity like fishing, poaching of their eggs and building near their nests.

Thousands of leatherbacks built nests at the Las Baulas beaches 10 years ago but the number has dropped to below 100 in the last five years.

Leatherbacks, which can reach a shell length of 5.6 feet and a weight of 1,543 pounds (700 kg), often die after being entangled in fishing lines and nets.

SAN JOSE, Costa Rica (Reuters) – Costa Rica, a leader in eco-tourism and home to some of the world’s rarest species, planted its 5 millionth tree of 2007 on Wednesday, December 19 as it tries to put a brake on global warming.

President Oscar Arias shoveled dirt onto the roots of an oak tree planted in the grounds of his offices, reaching the milestone in the Central American nation’s efforts to ward off what some experts say are the first signs of climate change.

By the end of the year, Costa Rica will have planted nearly 6.5 million trees, which should absorb 111,000 tons of carbon dioxide a year, Environment Minister Roberto Dobles said.

The country aims to plant 7 million trees in 2008 as part of the newly launched program.

Along with other green-minded nations like Norway and New Zealand, Costa Rica is aiming to reduce its net carbon emissions to zero, and has set a target date of 2021.

“I don’t know if we will end up being carbon neutral in 2021 as we have proposed, but the important thing is the audacity of the goal and the work we have to do,” Arias said.

Costa Rica is a magnet for ecology-minded tourists who come to visit the lush national parksand reserves that cover more than a quarter of the country and are home to almost 5 percent of the world’s plant and animal species including exotic birds and frogs.

Over the last 20 years forest cover in Costa Rica has grown from 26 percent of the national territory to 51 percent, though environmentalists complain that loggers continue to cut down old trees and that the national park system is under funded.

Costa Rican authorities have blamed the loss of more than a dozen amphibian species, including the shiny yellow “golden toad,” on higher temperatures caused by global warming.

Experts also say climate change is behind a spike in mosquito-borne diseases such as malaria and dengue fever at high elevations where they were once rare.

The number of dengue fever cases so far this year in Costa Rica’s high-altitude central valley stands at 3,487 — 86 percent higher than in the whole of 2006.

One of the largest of Central American, and Costa Rica’s largest, carnivores, an endangered species, it was once fairly common in coastal mangroves, lowland savannas, and wet and dry shrub lands and forest up to about 1000m elevation. But because its conspicuous tracks, the high value of its pelt, its reputation as a stock killer, and its vulnerability to hound pursuit and still hunting, this cat is now rare except in parts of large unhunted reserves. It occurs in Costa Rica on the Tortuguero, Santa Rosa, Corcovado and Rio Macho National Parks, and lower levels of Cordillera Talamanca.

Jaguars are rarely seen in daylight, but occasionally one suns on a cliff or log . They scratch tree trunks, but its not sure that they urine-mark objects or make territorial scratches on the ground. They are fairly aquatic and easily swim rivers, small lakes, and straits between mangrove islets. They favor damp sites such as streambeds in gallery forests, where footprints often reveal jaguar’s presence, approximate size , and travels. At any season jaguars of any sex may roar at night.

Although jaguars seem to prefer peccaries as prey, they also take monkeys, agoutis, deer, birds, fish, lizard, turtles, and other animals. Mud tracks reveal feeding on dead fish, alligators, iguanas and any other carrion left by receding waters.

Jaguars seem not to avoid the scent of a man, and one may follow a man walking in a trail. Although unprovoked attacks on men are rare, in Panama a jaguar recently charged a man who was carrying a bag of trapped birds.

The season of births probably varies regionally. Gestation is about 3 months, and the usual litter is two. Apparently males take no part on the rising of the young, which may accompany the mother for a year. Females reach sexual maturity at about 3 years of age and do not breed in successive years if their young survive. The main threat to the remaining jaguars in Central America is the clearing of forest for crops and grazing. When roads penetrate a primitive zone, the jaguar and white-lipped peccary ( Tayassu pecari ) are the first mammals to disappear. Jaguars seem to be poor colonizers of cutover lands or new areas regardless of the abundance of prey there. Jaguars range from northern Mexico to northern Argentina. The puma has much greater ecological and geographic range and occurs along with jaguars throughout Costa Rica.